Free software for the Macintosh. FrakKalk, the newest GoldfishSoft Program, is a fraction calculator for Mac OS X.
http://homepage.mac.com/goldfish1/
Calculator for solving a general quadratic equation.
http://www.1728.com/quadratc.htm
Reference programs written in VB3. Includes common mathematical formulas.
http://www3.sympatico.ca/prentice
Perform date math, calculate date differences, and organize data and events.
http://www.datecalculator.com/
Analysis is a tool that can draw 2D and 3D graphs of functions with different characteristics. Implicit f(x,y)=g(x,y)form curves are plot in a xy plane. Free download for all Windows versions
http://www.geocities.com/leibowitz.geo/analysis_en.html
A scientific calculator with full customizable user interface. Aalgebraic and RPN mode. Windows; shareware trial version.
http://www.pgcalc.net/
Extensive variety of software calculators collected in one directory. Scientific, graphing, loan and mortgage, currency and conversion calculators.
http://www.pc-calculators.com
Calculator resources including free download of scientific engineering, statistical, and financial calculators.
http://www.calculator.org/